Printing press control mechanism



6 Shee'lisl-Sheei 1 c. R. KADHELAND PRINTING PRESS CONTRQL MECHANISM Filed umn 11, 1942 f gas@ L 'mi @Inma Jan. 8, 1946.

Jan. 8, 1946.

C. R. KADDELAND PRINTING PRESS CONTROL MECHANISM Filed March 11. 1942 6 Sheets-Sheet 2 af W a7 INVENTOR. CMF/5 75N ,690054 Awa BY :am www Y ATTORNEY5 Jan. 8, 1946. c. n KADDELAND 2,392,391

PRINTING PnEss connor.. MECHANISM Filed March 11, 1942 6 Sheets-Sheet 5 FIG. 3a'

I NV E NTOR. CHP/5mn E 4005.4 ,cv/vp R BY @mfr/WL ATTORNEY .5

Jan. 8, 1946.

c. R. KADDELAND PRINTING PRESS CONTROL MECHANISM 6 Sheets-Sheet 4 Filed March 11. 1942 I N VENTOR.

ATTORNEYS Jan. 8, 1946. c. R. KADDELAND PRINTING PRESS CNTROL MECHANISM Filed March l1, 1942 6 Sheets-Sheet 5 1N VENTOR. He/.572W E man AMO M ma :f4/

ATTORNEYS Jan. 8, 1946, c. R. KADDELAND PRINTING PRESS (IGNTROL MECHANISH Fed UarGh 1ll 1942 6 Sheets-Sheet 6 INVENTOR. We/.575W A? oaaA/va g4/w www ATTORNEYS Patented Jan. 35.?, i946 PRINTING PRESS CGNTROL MECHANISM Christen R. Kaddeland. Shelton, Conn., assigner to Harris-Seybold-Potter Company. Cleveland, Ohio, a corporation of Delaware Application March 1I, 1942, Serial No. 434,182

(Cl. i-184) 19 Claims.

This invention relates to improvements in printing presses, more particularly to mechanism for controlling the impression of printing presses dependent upon the presence or absence of a. sheet at a point in advance of the printing point.

One of the objects of the invention is the provision o! mechanism of the type indicated which is particularly adapted lor use in multi-color presses.

Another object is the provision oi mechanism of the type indicated whereby the impression condition of each unit of a multi-unit printing press may be controlled independently of the impression condition in any of the other units.

Another object is the provision of sheet detecting means particularly adapted for use with an endless sheet conveyor having a multiple of sets of sheet carrying devices.

Another object is the provision of sheet detecting means which is posi ive in action and equally eilective upon different weights and grades o! stock.

Still another object is the provision. in association with sheet gppers, of sheet detecting means particularly adapted to detect the presence or absence of a sheet being presented by other grlppers.

Oth'er objects and features ol novelty will appear as I proceed with the description o! that embodiment of the invention, which, for the purposes o! the present application, I have illustrated in the accompanying drawings, in which:

Fig. l is a side elevational view partly in vertical longitudinal section or the delivery end of an endless conveyor shown in sheet transferring relation with the impression cylinder of the second unit of a multi-unit printing press. The section is taken substantially along the line l-l o1' Fig. 3.

Y. Fig. la is, in effect, an extension or Fis. l, showing the receiving end of the endless conveyor in sheet taking relation with the impression cylinder oi' the rst unit of the press.

Fig'. is a detail view on a larger scale of a gripper mechanism carried by the endless conveyor.

Fig. 3 is a. sectional view of the delivery drum oi' the endless conveyor. the sectionbeing taken substantially on the line -m-t of Fig. 4.

Fig. 3o is an evtension of Fig. 3.

Fig. l .is s. transverse sectional view through the delivery down showing certain of the parts in, the positions which they occupy when no sheet is in the grip-pers,

Fig. 5 is a detail sectional view of a. control plunger.

Fig. 6 is a detail sectional view on a larger scale of the sheet detector mechanism when at its normal position, a sheet being held in the grippers.

Fig. l is a fragmento] plan view of the same.

Fig. 8 is a view similar to Fig. 6 but showing the condition of the parte when there is no sheet in the srippers.

Fig. 9 is a plan View of the same.

Fig. 10 is an end view of the delivery drum showing the adjacent impression cylinder and its throw-oil mechanism, illustrating the parts in normal position.

Fig. 11 is a. similar view with the impression oil.

Fig. 12 is a sectional view taken substantially on the line I 2-I2 of Fig. 10, and

Fig. 13 is a View similar to Fig. 12 but taken on the line iB--II of Fig. 1l

In the drawings 2li is the impression cylinder of the rst unit of any pair of successive units of a multi-unit printing press. Sheets are ted individually to cylinder 2D by a feeding transfer drum 2l or by any other suitable means capable of presenting them to the grippers 22 ot cylinder 20. These grippers convey the sheets into contact with a printing cylinder 23. which in this 'case may be the form cylinder of an intaglio printing unit, the grippers 22 being recessed slightly below the periphery oi cylinder 20 so that they may pass cylinder 23 in case the latter is a full cylinder.

After taking an impression from cylinder 23. the sheets are transferred by grippers 22 to an endless conveyor. referred to generally as 2|. which conveys them to the grippers 25 of the impression cylinder 26 oi the second printing unit oi the press. The sheets are carried by cylinder 2li into contact with form cylinder 21, from which they take a second impression, after which they are transferred by grippers 25 to the grlppers i8 or a further conveyor, which may be a second endless conveyor similar to conveyor 2l, the receiving drum of which is indicated at I9. This latter conveyor carries the sheets to a succeeding operating point, as for example to another printing unit, or to a. delivery mechanism.

The rst of the two printing units illustrated is mounted in a frame, one member of which is shown et 29 in Fig. 1a. The second printing unit is likewise mounted in a frame, one member of which' is shown at 30 in Fig. 1 and the other at 3l in Figs. 10 and 11, these frame members being illustrated also in Figs. 3 and 3a. Driving mechanism, not shown, is provided for rotating the cylinders and the conveyor drums in the directions indicated in the drawings.

The conveyor 24 comprises a pair of parallel chains 82 and 33 at opposite sides of the press, to which are secured a plurality of gripper support bars 84 whose ends are formed into plates 35 having slots to receive pins 3S of the chains 82, 88, These chains trave" around Sprocket wheels 31, 38 which are bolted or otherwise secured to the ends of the conveyor drum 88,

As best seen in Fig. 3, cylinder 39 is provided at one end with a hollow shank 40 in which is secured a stud 4I which carries an anti-friction bearing 42 mounted in a bore 43 of frame member Il. At its other end, as shown in Fig. 3a, drum 38 has a hollow shank 44 in which is secured a stud 45 carrying an anti-friction bearing 48 which is held against axial movement in bore 41 of frame member 38. Stud 45 at its outer end also carries a gear 48 which forms one of the elements of the driving mechanism previously referred to.

At the rear end of the conveyor, chains 82 and 88 are trained around a pair of sprocket wheels, one of which is shown at 48, Fig. 1. these sprocket wheels being secured to the ends of a conveyor drum 58 which is rotatably mounted in the frame of the first printing unit.

The drums 38, 50 rotate once for each revolution of the impression cylinders, and the gripper bars 3i are so spaced along the chains 32, 33 that a bar receives a sheet from the impression cylinder 20 upon each revolution thereof and that a bar delivers a sheet to the impression cylinder 25 upon each revolution of that cylinder. Each of the drums 88, 50 is formed with a recessed portion i to accommodate a gripper bar and its associated mechanism.

Near each of their ends the drums 88, 58 are formed with upstanding lugs 52. 53 having oppositely disposed beveled faces 54 for accurately positioning the bars 84 as they travel around the drums. Between the beveled faces 54 each of the drums is provided with a nat area 55. Each bar 84 is formed at its sides with beveled faces 58 (Fig. 2) arranged to fit between the faces 54 and permit the bars to be clamped against the flat area 55.

Mechanism of any suitable type, as for example that disclosed in my oopending application. Serial No. 409,547 filed September 4, 1941, may be provided for momentarily clamping the bars 84 to drum 58 during the time that the grippers of each bar are receiving a sheet from impression cylinder 28 and for clamping them to drum 88 as the bars travel around that druni prior to and during delivery of the sheets to the impression cylinder 28. The bars 84 are held against sidewise movement by the beveled faces 51. 58 provided on sprockets 31, 88.

Formeciintegral with each bar 84 are bearings 58 which support a gripper shaft 88. The latter has keyed to it a plurality of gripper dogs 8i. Associated with each dog except one, preferably the center one, there is a gripper finger 82 pivotally mounted on the shaft and urged toward closed position by spring 83 which forces rod 64 against rounded heel 85 of gripper 82, the other end of the spring bearing against the bottom of a hollow socket 88 which is pivotally connected to dog 8| at 81 and bears against the upper face of gripper support har 84.

The grippers 82 bear against gripper blocks 88 formed in two bars 88 which are secured by -tion .above referred to.

screws 1li to the gripper support bar 34. All the grippers are opened and closed at the proper times by a rocking movement of shaft 8u imparted by mechanism not herein shown in detail but more iully disclosed in my copending applica- 'I'his mechanism comprises a lever 1I which is keyed 'to shaft 50 and extends inwardly through an opening 12 in the drum 39 or 5D, as the case may be. This arm carries a roller 13 at its lower end which coopcrates with the gripper operating mechanism. Lever 1l is provided with an abutment 14 which bears against one of the bars 69 to limit movement of the shaft 60 in one direction.

The central one of the grlppers, marked 82', and its associated sheet detecting mechanism will now be described. The two bars 59 are spaced apart somewhat at the middle of bar 84 and interposed between them there is a block 15 which is secured by screws 18 to bar 34, This block is provided with a bore 11 (see Figs. 6 and 8) which slidably accommodates the shouldered portion 18 of a detector plunger 18. The lower end of the latter is slidably guided in bore 8|) of block 15, while the upper portion is similarly guided by the bore 8i of a plug 82 that is threaded into block 15 to close bore 11. A spring 83 is confined between the plug 82 and the plunger shoulder 18, thereby tending normally to force the plunger 18 to its lowermost position with its shoulder 18 against the bottom of the bore 11. The block 15 is cut away centrally at its upper end to form a slot 84 of sufficient width and depth to accommodate the plug 82 and to provide space for the end of the pivoted detector finger, later referred to, when the latter is positioned below the sheet and the gripper 62', Fig. 8. The upper part of block 15 at each side of slot 84 is beveled as at 85 also for the purpose of providing clearance for the detector finger. Thus there are formed at the top of the block two lands 86 which form the surfaces against which the sheet is clamped by gripper 82'. outwardly of each of these lands 88 the block 15 is cut away to form low shoulders 81 which provide clearance for the opening of grippers 22 as the latter transfer a. sheet to grlppers 82 and 82', and likewise for the open grippers 25 when a sheet is transferred from the conveyor to impression cylinder 28.

Gripper 82' is bifurcated, the space between the bifurcations being of approximately the same width as the slot 84 of block 15 and extending sufficiently far back to permit the upper end oi' plunger 18 to pass upwardly through it (see Fig. 8). The end of the gripper 62' is thus formed in two spaced portions 88 which cooperate with lands 88 of block 15 to grip the sheet.

Block 15 carries two ears 88 which support a pin 98 upon which a detector finger 8| is pivotally mounted by means of a pair of integral lugs 82. A spring 88 bearing against the bottom of a hole in block 15 and against the' upper part of detector finger 8| tends to move the latter about its pivot in the clockwise direction, which movement is limited by the engagement of an abutment 84 on the finger with the face of block 18. The upper portion of finger 8| is bent forward, that is in the direction of movement of the sheet, to present a substantial surface area parallel to and adjacent the piane of a sheet S being presented to the grippers 82, 82', so that the nngeris contacted by the surface of the sheet rather than by the edge thereof.

The finger 9| occupies either of two different positions, depending upon whether or not a sheet i is gripped between the grippers and the gripper pads, these two positions being illustrated in Figs. 6 and 8. The upper end oi the nnger is narrower than the body portion thereof, with shoulders Si therebetween so located that when the finger 9i is in the position corresponding to the presence of a sheet, as shown in Figs. 6 and 7, these shoulders It lie under the ends of the spaced gripper portions 88. Beyond these shoulders the nnger 8| is provided with a biiurcated extension 8l slightly narrower than the slot B4 and the corresponding slot in the gripper 62', which extension 9| is sumciently long to project under the gripper 82', as shown in Figs. B and 1. Thus, when a sheet is present, the detector finger 2| is positively held against movement in the clockwise direction by the fact that gripper $2' overlies extension I as well as shoulders l5.

The slot I1 between the bifurcations of detector ringer 0| is of sufiicient size to permit the passage of plunger 19 therethrough when the ringer 9| is in its position corresponding to the absence o! a sheet, that is in the position of Figs. B and 9. This slot 01, however, is so located that when nger Il is in its position corresponding to the presence of a sheet, as in Figs. 6 and '1, the plunger strikes against nnger 9i and is prevented from passing upward through the plane o! the sheet. The length of the extension 98 and the location of the shoulders 85 are such in relation to gripper 82' that when the finger 9| is in the position of Figs. B and 9, gripper B2' is free to open and close without affecting ringer 9|, but when a sheet is present, as in Figs. 6 and '1, the nnger 9| is moved by the sheet counter-clockwise and is clamped rmly in that position by the gripper 82.

In order to make use oi' the position of detector finger 9|, in other words in order to make the machine function in accordance with the presence or absence of a sheet in a set of grippers, mechanism is provided within and upon the forward drum I9 of the conveyor for controlling the impression or the second unit or the press. This mechanism will now be described.

About midway of the length of drum 38 there is a bracket IDI which extends across the body oi the drum and is fastened by bolts |02 at each end to lugs IDI integral with the wall of the drum. The bracket lui forms a central bearing for a shaft IM, the ends of which are journaled in the ends of the drum. At the right-hand end, as viewed in Fig. 3a, shaft IM carries an arrn |05 clamped to the tapered end of the shaft by a nut |08. On the outer end of arm il!! there is a roller |01 which runs in the groove IBB oi a cam plate |09 which is secured to the frame member 30. By means of the mechanism just described the shaft IM is given a complete oscillation forward and backward for each revolution of the drum $9.

Keyed to shalt |04 and adiacent bracket il is a lever ill carrying a pin on which is pivotally mounted a double-ended pawl H2 which is biased in the counter-clockwise direction, as viewed in Figs. i and 4, by a compression spring ||2 carried on spring rod Ill. One end of this rod is pivoted at IIB to pawl i i2. and the other end passes loosely through a hole in an oscillatable pinA HB mounted in lever Ill. Spring lil is confined between the head of its spring rod and the pin H6. and the latter pin extends into the path ci pawl H2 to limit the movement o! the latter in the counter-clockwise direction under the influence o! the spring.

As shaft I oscillates, the lever HB and the pawl H2 are likewise oscillated back and forth. The end |i1 of pawl H2 is adapted in one of its extreme positions to engage an intennediate plunger H8 which, as illustrated, is of rectangular cross-section and is arranged to slide in a slot lil formed in a boss in that is integral with bracket IM. Plunger HI is cut away for part of its length to form a recess i2! in which is placed a compression spring |22, the lower end o! which bears against the bottom of recess |2| and the upper end ot which bears against a small cross bar |23 situated in a slot extending crosswise of the boss and secured in place by a pin or a screw |24. A plate held in place by screws |28 connues the spring |22 and the plunger HI. Thus it is seen that the plunger Il! is biased downwardly by the spring |22 but may be lifted against the action of that spring by the end H1 oi pawl H2. When a gripper supporting bar comes into position in the cavity il o! the drum, intermediate plunger IIB and detector plunger 19 come into alignment. A head |21 on the outer end of plunger il! is shaped to enable plunger 19 to properly engage plunger lit as the gripper bar Il moves into position between the beveled faces 5l of the drum.

The pressure of spring H3 tending to rotate pawl H2 counter-clockwise is sufilcient to overcome the pressure or springs |22 and B3. Hence when no sheet is present in the grippers and plunger 19 is accordingly free to move upwardly through the plane which would ordinarily be occupied by a sheet, pawl end H1 will raise both plungers Ill and 'I8 each time the lever lib is rocked to its right-hand position.

The opposite end |28 of pawl H2 is arranged to engage s. notch |29 in a segment arm |20 which is pivotally mounted on shaft IM between lever ill and bracket ii. Segment arri |10 is provided with an abutment l2| which cooperates with an abutment |22 on lever H0. so that when the lever H0 is oscillated toward the right from its dotted-line position in Figs. 1 and 4, segment arm |30 will likewise be moved toward the right,

lli)

'- moving arm |20 to the left and its movement in that direction being limited by the engagement of a further abutment |33 forming a part of arm |30. against a lug |24 on bracket III. It will be seen that so long as the pawl end |20 remains in engagement with notch I2! ci arm t the latter arm will be osciilated back and forth between the dotted-line position and the solid-line position of Figs. 1 and 4, the pawl lever iil moving it to the right.

Arm |20 has formed thereon a gear segment IIB which meshes with a pinion ISB fixed upon a rod |31. This rod is oscillatably and rotatably mounted, being supported at one end in a bore through the center of stud 4| and at the other end in a sleeve |82 which has a steep pitch screw thread |38 that meshes with a mating thread Nil in a bracket ill which is secured by bolts |42 to cross bracket IM. Between the pinion ill and the sleeve III is a tubular member |43 which surrounds rod |21. The pinion III. tubular member ill, and threaded sleeve lll are clamped in rigid relationship endwise upon the rod |31 by nuts i and i which engage threaded portions oi rod |21. The tubular member i is rotatably and oscillatably supported by the cross bracket |ill. As pinion ISI is rotated, first in one direction and then in the other, by gear segment lil, the rod |31 is caused to move endwise between the solid-line and dotted-line positions shown at the left of Fig. 3. Segment |35 ordinarily does not oscillate and hence pinion |38 does not turn relative to the drum. Consequently rod |31 ordinarily remains in the full-line position of Fig. 3. It is only when pawl end |28 engages notch |28 that arm |88 moves with lever 8, and this occurs only when plungers H8 and 18 are free to move outwardly, in other Words, when there is no sheet in the grippers that are traveling around the drum 38 at the time.

The forward and backward movement of rod |31 is utilized to control the impression mechanism of the second printing unit by means which will now be described with reference particularly to Figs. 10 and 11 of the drawings. Shaft |58 of impression cylinder 28 is rotatably mounted in eccentric bearings in each of the frame members 84, 3|, one such eccentric being shown at |8|. The latter eccentric carries a pin |52 to which is pivotally connected one end ot a link |88, the other end of which carries a sleeve |84 which is adjustably clamped to the link |58 by clamping nuts |88 and |88. Sleeve |54 is pivotally ccnnected by a pin |81 to a lever |88 which is keyed to one end of shaft |88 extending across the press and Journalled in frame members 88, 3|. At the opposite side oi' the press parts similar to those Just described are provided, that is the other end of shaft |58 is iournalled in an eccentric similar to eccentric iii, and connections between that eccentric and shaft |88 are provided similar to link |83,sleeve |84, and lever |58.

It will be seen that movement of shaft |58 alters the position of the lever and link connections at the opposite sides of the machine, thus rotating the eccentrics in which the impression cylinder 28 is journalled, so that the latter cylinder is moved toward and away from the form cylinder 21. With the parts as shown in Fig. 18 impression cylinder 28 and form cylinder 21 are in printing relation. As shown in Fig. 11, iinpression cylinder 28 has been moved away from form cylinder 21 to avoid printing on the bare impression cylinder when no sheet is carried thereby. Preferably connections should be provided i'or displacing the drum I8 or other device which carries grippers 2l by an amount suillcient to maintain a iixed relation between the drum and the impression cylinder, so that there will be no interference between those grippers 28 or drum I8 and the impression cylinder 28, but for the sake of simplifying the disclosure, such connections are omitted from the drawings in this case.

For operating shaft |88 and thereby displacing cylinder 28, the lever |58 is provided with two studs |88 and |8| on opposite sides oi' the shaft III, and a two-sided hook member |82 is arranged between these studs to selectively engage one or the other thereof and thereby impart limited rotation to the lever |55. Hook member |82 is given periodic up and down movement by a cam lever |83 to which the hook member |82 is pivotally Joined at its upper end by pin |84. Cam lever |83 carries a roller |88 which travels on a cam |88 secured to the end of drum stud 4|, as later described. Lever |83 is pivotally mounted on stud |81 secured in frame member 3|, and is equipped with a short arm |88 to which is pivotally secured one end of a spring rod |88, the other end of which slides in an opening in stud |18, oscillatably mounted in frame member 3|. Spring |1| surrounds rod |88 and operates to cause roller |85 to follow its cam.

As mentioned above, the hook member |82 is arranged to swing on its pivot |84 so that one of its shoulders, |12, may engage stud |88 to lii't the latter. or the other of its shoulders, |13, may engage the stud |B| to lift that stud. The position of member |82 is controlled by a rod |14 which slidably extends through perforated stud |15 oscillatably mounted in hook member |82. Collars |18, |11 are fixed to rod |14 and a compression spring |18 is confined between collar |11 and stud |18. When rod |14 is moved to the right from the position shown in Fig. 10, it pushes hook member |82 against pin |8l, any excess movement of rod |14 being absorbed by compression spring 18. When rod |14 is moved to the left from the position shown in Fig. 11. it swings nember |82 toward the left and against stud 8.

Rod |14 is pivotally connected to the lower arm of a bell crank |18 which is mounted for oscillation upon a stud |88 fixed in a bracket |8| that is bolted to frame member 3| by bolts |82. The upper arm oi' bell crank |18 carries a pin |83 to which is connected spring rod |84, the other end of which passes loosely through a hole in a stud |88 whichis oscillatably mounted in frame member 3|. Between a collar |88 on rod |84 and the stud |85 is a compression spring |81 which biases bell crank |18 in the clockwise direction, its movement in that direction being limited by the collar |18 on rod |14, as shown in Fig. i8. The upper end of bell crank |18 is also provided with a transversely rounded lower face |88 which is arranged to be engaged by the beveled end |88 of the head |88 of sliding rod |31. The head |88, as shown in Fig. 3. extends through the center of clamping ring |8| located in a counterbore of cam |82 carried on the end of the drum stud 4|. Screws |83 extend through ring |8I into the end of stud 4| to clamp cams |82 and |88 and the inner race of anti-friction bearing 42 against the shoulder of shank 48.

Cam |82= has a circular portion |84 which extends i'or somewhat less than three-quarters of its circumference. a portion 85 sloping toward the cam axis and a portion |88 sloping in the direction of its axis. These three surfaces of cam |82 cooperate with a pin |81 (see Figs. l2 and 13), slidably carried in a hole in the upper end of bell crank i 18. This pin has a reduced central portion |88 forming a recess into which projects a stop pin |88 driven into the bell crank |18 and cooperating with the shoulders of the recess of f pin |81 to prevent the latter from moving beyond a certain desired position in either direction.

When pin |81 is in the position of Fig. 13, it functions as a follower for cam |82. Part of the time its side wall contacts the periphery of the cam and Part of the time its inner end contacts the face oi' the cam. While it rides on the circular periphery |84, it maintains bell crank |18 raised, as illustrated in Fig. ll. When it rides down the slope |88, it permits bell crank |18 to swing clockwise to the position shown in Fig. l0. When it contacts the slope |88, it is slid outwardly from its Fig. 13 position to that of Fig. 12, the fiat spring 288 carried by bracket |8| being shaped to permit this outward movement of pin |81, as shown in Fig. l2. Whenever the bell crank |18 is raised to its upper position. spring 288 resiliently pushes pin |81 to its inner position, as shown in Fig. I3.

Operation.-Assuming that the press is in norn mal operation, that is sheets are being fed in regular succession and being printed on each of the printing units, the impression throw-ofi mechanisrn will occupy the position ilustrated in Figs. 10 and 12. Under these conditions impression cylinder 25 is in printing relation with form cylinder 21, being held in this position by the link and lever arrangement connecting eccentric and shaft |59, the pins |52 and |51 being in substantial alignment with the shaft |59. Hook member |62 is raised and lowered during each revolution of the press by cam |66 and is held in sliding contact with stud |60 by the pressure of spring |81 acting through bell crank |19 and connecting rod |14.

After each sheet is printed by the impression cylinder 2|I of the first printing unit, it is transferred by grippers 22 to one of the sets of conveyor grippers 62, 62. During the transfer operation the sheet is supported at rather closely spaced points along its forward edge by the grip-E per pads 22' and their associated grippers 22 so that the Zone directly behind the forward edge and between the grippers may be said to be straight and taut, that is, this zone is firmly held by the grippers against any substantial displacement by an object pressing against the sheet. This portion of the sheet engages the upper forwardly directed surface of detector finger 9|, swinging the latter upon its pivot 90 and depressing it sufficiently to cause the sheet and nger 9| to lie under the gripper B2 as the latter cioses. When the gripper 62' closes upon the sheet, its forwardly extending portions 8B overlie the shoulders 95 of the detector finger and the central portion of the gripper 52' overlies the blfurcated end 9B of the detector finger so that the gripper 62' firmly holds the detector iinger 9| in the position shown in Fig. 6. After transfer of the sheet, the grippers 62, 82 and .the associated gripper bar 34 leave the taking drum 50 and are conveyed by the chains 32, 33 towards the delivery drum 39.

Somewhat before the gripper bar 34% reaches the drum 39 the shaft lill is oscillated by cam |08 to swing lever |||J and its associated pawl ||2 into the position shown in Fig. 4, in which the pawl end is in engagement with intermediate plunger ||8. As the gripper bar 34 carrying the sheet moves into cooperation with drum 39 and is clamped thereto between the sloping faces 54, the detector plunger 19 comes into contact with the head |21 of intermediate plunger H8, which has been lifted by the pawl end ||1 through the action of its spring ||3 into the position shown in Fig. 1. the plunger spring |22 being slightly compressed. Owing to the fact that plunger 19 cannot be forced upward in block 15 due to the fact that its upper end strikes against detector finger 9|, this plunger 19 acts upon plunger I I8 to force the latter down against the upward pressure of pawl end ||1. This results in turning pawl ||2 so that its other end |28 is raised out of engagement with notch |29. Subsequently and shortly after the position illustrated in Fig. l the shaft IM is osclllated to the left by the cam |98. Ow-

ing to the disengagement of pawl end |29 and notch |29, however, the arm |39 and its associated gear sector |35 are not disturbed but remain in the full-line position illustrated in Fig. l. The pinion |36 likewise remains stationary. with the result that no movement is transmitted to rod |31 which remains` retracted in its Fig. 3 full-line position, The .bell crank |19 is thereby permitted to remain in its extreme clockwise position, as shown in Fig. 10, thus maintaining the lower end of hook member |62 to the left against stud |50, with the result that the impression mechanism is kept in the "on position. When the grppers 62, 82' reach the proper position, they transfer the front end of the sheet to grippers 25 on impression cylinder 28 and the latter conveys the sheet into Contact with the form cylinder 21 and subsequently transfers it to the further grippers 28 which convey the sheet to the next operating point.

So long as each sheet is properly transferred from the first impression rylinder 2li to one of the sets of conveyor grippers 82, 62', the operation of the mechanism will continue as Just described. But if for any reason the grippers 22 fail to present a sheet to the conveyor grippers 62, B2', as when the feeding of sheets to the press is stopped, or a sheet is improperly fed, the detector linger 9| of that set of grippers remains in the position which it normally occupies under the inliuence of spring 93, that is in its extreme clockwise position as shown in Fig. B. As the gripper unit carrying no sheet comes into ensagement with drum 39 and is clamped thereto, the detector plunger 19 engages the head |21 of intermediate plunger ||8 as before, butin this case, owing to the absence of a sheet and the fact that detector finger 9| lies outside the path of movement of plunger 19, the latter plunger is pushed upward through the slot in the end of gripper E2' to the position shown in Figs. 8 and 4 by the pawi end lll, acting through the intei-mediate plunger |||l. As previously stated, the pawl spring ||3 is of sufficient strength to overcome the intermediate plunger spring |22 and the detector plunger spring 83 when the plunger 19 is free to move upwards. The pawl ii! is thereby permitted to remain in the position shown in Fig. 4, with its end |28 remaining in engagement with the notch |29. Shortly following the position iilustrated in Fig. 4, the cam |08 oscillates shaft |04 to the left and swings the .lever ||9 and its pawl ||2 to the dotted-line position shown in that figure. This movement is imparted to arm |30 and its gear segment |35 which results in the rotation or pinion |35 and through the agency of the steep pitch intermeshing threads |39 and |48 causes the rod |31 to move towards the left in Fig. 3 to the position shown in dotted lines. This movement brings the tapered end |89 of rod |31 into engagement with the rounded portion |88 of bell crank |18. to cause the upper arm of the bell crank to be raised to the position illustrated in Figs. 11 and 13. 'nie upward movement of this arm brings sliding` pin |91 into contact with the spring 299. which pushes the pin resiliently toward the cam |92. As soon as the bell crank |19 is turned suiliciently to bring the pin |91 above the circular periphery |94 of the cam |92, the pin |91 is snapped toward the right by spring 20|) into the position shown in Fig. 13, where it overlies the cam |92. The counter-clockwise movement of boli crank |19 thus caused by rod |31 in turn causes rod |14 and spring |18 to move toward the right in Figs, l0 and 11 to resiliently torce the hook member |62 to the right and into contact with the stud |8I. Upon the next upward movement of hook lever |62 caused by cam |86, the shoulder |13-will engage stud |6| and lift the latter, thus turning the shaft |59 in the counterclockwise direction to the position shown in Fig. 11, This movement causes rotation of the impression cylinder eccentrics in a direction to raise the impression cylinder 26 away from the form cylinder 21, so that their printing relation is destroyed. Thus when the grlppers 62, 62 fail to transfer a sheet to the grippers 23 of the second impression cylinder 26, the throw-oi! mechanism is operated to move the latter cylinder out of printing relation so that no printing is placed upon the bare cylinder.

So long as each successive set of grippers 32, 32' fails to receive a sheet, the detector plunger 1l will be permitted by detector linger 3| to be raised by the upward pressure oi' pawl |i2 acting through plunger I I3, thereby causing the pawl end |23 to remain in engagement with its notch |23 of arm |33, thereby transmitting the oscillation of shaft |33 through gear sector |33 and pinion |33 to the rod |31 which will continue to be moved outward at each revolution of the drum 33 to the dotted-line position shown in Fig. 3. The rod |31 will be moved back and forth upon each revolution in one direction due to the continued engagement of pawl end |23 and notch |23, and in the opposite direction due to the engagement of abutment |32 of lever lili with abutment I3| of arm |33.

During the time the rod |31 is retracted into the solid-line position of Fig. 3, the outer periphery |34 of cam |32 cooperates with sliding pin |31 to hold the upper arm of bell crank |13 raised as illustrated in Fig. 13. During the time the cut-away portion of cam |32 corresponding to the slopes |33 and |33 is adjacent to pin |31, the rod |31 is in its extended position, as shown in dotted lines in Fig. 3. Thus, as long as no sheets are fed, the bell crank |13 is maintained in its anticlockwise position at all times, thus maintaining the lower end of hook lever |32 to the right in contact with stud |3|.

Upon the resumption oi the feeding of sheets. whereby a sheet is presented by the grippers 22 to one of the sets of conveyor grippers 32, 32', the detector plunger 13 associated with that set is prevented by finger 3| from being pushed upward, so that when it comes into engagement with the intermediate plunger |I3, the pawl ||2 is tilted to raise its end |23 out of the notch |23 so that the motion of lever |i3 is not transmitted to the arm |33, and the sliding rod |31 remains retracted within the drum 33. As the drum 33 continues to rotate, carrying with it the cam |32, the slope Ill of the latter cam comes into line beneath the pin |31 and owing to the pressure of spring |31, the latter pinfollows the incline |33 downward and the bell crank |13 swings clockwise toits Fig. l position. As cam |32 continues to rotate, the slope |33 comes into engagement with the nd or pin |31 and pushes the latter pin to the le in the bell .crank until it occupies the position shown in Fig. l2. Thereafter. if sheets continue to be fed to each of the sets of grippers 32, 32', the rod |31 remains retracted within the drum 33 and the bell crank |13 remains in its extreme clockwise position, thereby maintaining hook member |32 against stud |33 as it travels up and down. The first upward movement of hook member |32 subsequent to the initial clockwise rotation of bell crank |13 acts to raise stud |33 and throw the printing impression on between cylinders 23 and 21,

In the embodiment described, it is to be noted that each of the plurality of sets of grippers which, together with the chains, comprise the conveyor for conveying sheets from the nrst unit to the second, is provided with a detecting device which assumes one condition when a sheet is present in the grippers, and another condition when a sheet is absent, and as each of the sets of grippers approaches the succeeding printing unit,

aaeasoi its detecting device cooperates with further detecting devices in the conveyor drum associated with that unit, to control the impression mechanism in accordance with the condition of each of the nrst detecting devices. Thus one part of the detecting mechanism is set at the point where the grippers receive a sheet, and this part is carried to a remote point where it actuates the other part of the detecting mechanism.

Although in some of its aspects the invention is particularly applicable to flexible conveyors. as disclosed in the drawings, it is obvious that the detector mechanism herein disclosed may be employed in connection with any set of sheet grippers on a cylindrical transfer device employing one or more sets of srippers, as well as upon a flexible conveyor, or, in fact upon cylinders other than transfer cylinders, such, for example, as

" impression cylinders. i

It is also obvious that the cylinder 23 instead of being an impression cylinder may be merely a feeding cylinder which conveys the sheet from some previous point in the machine to the grippers which convey the sheet to the impression cylinder 23,

Having thus described my invention, I claim:

l. In sheet handling mechanism, a sheet gripper finger and pad, means for presenting sheets to said gripper and pad with their forward portions transversely taut, a detector finger associated with said gripper and pad on the side of the sheet path remote from the gripper finger; said detector nnger being biased toward one position and having a portion adapted to present a substantial surface area to the taut surface of the advancing sheet, whereby the finger is deflected toward another position, and control means functioning in response to the position of'said detector finger.

2. In sheet handling mechanism, a sheet gripper finger and pad, means for presenting sheets to said gripper and pad with their forward portions transversely taut, a detector finger associated with said gripper and pad on the side of the sheet path remote from the gripper nnger, said detector nnger being biased toward one position and having a portion adapted to present a substantial surface area to the taut surface of the advancing sheet, whereby the finger is deflected Y toward another position, and control means functioning in response to the position of said detector finger, the parts being so constituted and arranged that when a sheet is taken, said gripper miler act! to hold said detector ngcf' in deccted position.

3. In a printingmachine, a printing couple, means for conveying sheets to said printing couple comprising a set of traveling sheet grippers, means for feeding sheets to said grippers at a given point in their travel, a sheet detector finger traveling with said gripper! arranged to assume at that point either of two positions depending upon whether or not a sheet is taken from said feeding means, and mechanism functioning at a point with respect to the direction of sheet travel substantially spaced from said firstnamed point for controlling the impression of said printing couple, the operation of said mechanism being dependent upon the position of said Eel'.

4. In a printing machine. a printing couple. throw-oi! mechanism therefor, means for conveying sheets to said printing couple comprising a set of traveling sheet grippers, means for feeding sheets to said grippers, a sheet detector finger traveling with said grippers arranged to assumo asoaaoi either of two different positions depending upon whether or not a sheet is taken from said feeding means, and means associated with said conveying means at another point thereof for detecting the position of said nger, said last-named means functioning when no sheet is in the grippers for initiating the operation of said throw-off mechanism.

5. In a printing machine. a printing couple, an endless conveyor comprising a set of sheet grippers arranged in alignment transversely of the conveyor, means at one end of the conveyor for feeding sheets to said grippers, a sheet detector finger traveling with said grippers arranged to assume either of two different positions depending upon whether or not a sheet is taken from said feeding means, and control mechanism at the opposite end of the conveyor responsive to the position of said linger.

6. In a printing machine, a printing couple, an endless conveyor therefor comprising a plurality of sets of sheet grippers, means for feeding sheets to said grippers, a sheet detector nger traveling with each set of -grippers arranged to assume either of two different positions depending upon whether or not a sheet is taken from said feeding means by that set of grlppers, and mechanism associated with said conveyor at a point remote from said feeding means for controlling the impression of said printing couple, the functioning of said mechanism being dependent upon the position of each finger as it passes said point.

7. In a printing machine, a printing couple, an endless conveyor comprising a set of sheet grippers, a finger traveling with said grippers mounted to swing on an axis transverse to the direction of travel, means for feeding sheets to said conveyor in a transversely taut condition comprising grippers staggered in relation to said conveyor grippers, one end of said finger being sprix: g-biased to a given position and being swung to another position by the engagement of a sheet as it is transferred from the feeding grippers to the conveyor grippers, and control means associated with said conveyor at a point remote from the sheet-taking point, said control means functioning in response to the position of said finger.

8. In a' printing machine, a printing couple, an endless conveyor comprising a set of sheet grippers. a finger traveling with said grippers mounted to swing on an axis transverse to the direction of travel, means for feeding sheets t said conveyor comprising grippers staggered in relation to said conveyor in a transversely taut condition grippers, said finger being spring-biased to a given position and being arranged to present a substantial surface to the surface of a sheet being taken from said feeding means, whereby the linger is swung to another position by the movement of the sheet into said conveyor grippers. and control means associated with said conveyor at a point remote from the sheet-taking point. said control means functioning in response to the position of said finger.

9. In sheet-handling mechanism, a set of sheetfeeding grippers and a set of sheet-receiving grippers. the grippers of one .set being staggered with respect to those of the other seine. finger associated with one of the grippers of the receiving set mounted to swing about an axis transverse to the direction of travel of the sheet, said finger being arranged to present a surface of substantial extent to a surface of the sheet while the latter is held taut by the feeding grippers on opposite sides of said nager. whereby the finger is swung upon its axis by the transfer of a sheet from the feeding grippers to the receiving grippers, and control means responsive to the position of said finger.

i0. In sheet-handling mechanism, a set of sheet-feeding grippers and a set of sheet-receiving grippers, the grippers of one set being staggered with respect to those of the other set, a finger associated with one of the grippers of the receiving set mounted to swing about an axis transverse to the direction of travel of the sheet, said finger being arranged to present a surface of substantial extent to a surface of the sheet while the latter is held taut by feeding grippers on opposite sides oi said finger, whereby the finger is swung upon its axis by the transfer of a sheet from the feeding grippers to the receiving grippers, the receiving gripper associated with said finger overlying said finger after the latter is swung on its axis, whereby the linger is positively held in its deflected position, and control means responsive to the position of said finger.

ii. In a printing machine, sheet conveying means comprising a set of sheet grippers arranged in alignment transversely of the conveying means, means for feeding transversely taut sheets to said grippers at one point in the travel of the latter, a finger associated with one of said grippers mounted to swing on an axis transverse to the direction of movement of the sheet. one end of said finger being bifurcated and bent over toward the direction of movement of the sheet to present a surface of substantial extent to a surface of the sheet, whereby the linger is swung on its axis by the advancing sheet, one of the receiving grippers being biiurcated and overlying said finger in its deflected position for positively retaining the iinger in that position, a plunger on the conveying means capable of passing through the bifurcations of said gripper and finger, said plunger abutting said finger when deflected, and control means associated with said conveying means responsive to the capacity of said plunger for moving or not moving through said gripper and linger bifurcations.

12. In mechanism of the character described. a drum, sheet grippers associated with the drum, a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillation to said rod, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, detector mechanism operatively associated with said grippers, said means for oscillating said rod being responsive to the condition of said detector mechanism, and throw-off mechanism responsive to axial movement of said rod.

13. In mechanism of the character described, a drum, sheet grippers associated with the drum, a rod axially mounted in the drum for axial and oscillating rotational movement with respect to the drum, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, a lever within the drum, means for imparting a complete oscillation thereto for each revolution of the drum, drive mechanism for imparting rotary oscillation to said rod from said oscillating lever, detector mechanism associated with said grippers, means responsive to the condition of said detector mechanism for controlling said drive mechanism, and throw-off mechanism responsive to axial movement of said rod.

14. In mechanism of the character described, a drum, sheet grippers associated with the drum,

a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillati `n to said rod, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to the rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, and impression throw-oil mechanism arranged to be set in operation by the outward movement of the rod.

15. In mechanism of the character described, a drum, sheet grippers associated with the drum, a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillation to said rod, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to said rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, and impression throw-ofi mechanism arranged to be set in operation toward impression-off position by the outward movement of the rod, said throw-oil mechanism comprising means for automatically maintaining itself in impression-off position during the inward movement o! the rod.

16. In mechanism of the character described. a drum, sheet grippers associated with the drum, a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillation to said rod, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to said rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, impression throw-oil mechanism arranged to be set in operation toward impression-oil' position by the outward movement of the rod, said throwoil' mechanism comprising means for automatically maintaining itself in impression-off position during the inward movement of the rod, and means for automatically shifting the throw-oli UERTIF GATE Gif Patent No. 2,592,591.

mechanism to impression-on position when the rod fails to rotate.

17. In mechanism of the character described, a drum, sheet grippers associated with the drum. a rod axially mounted in the drum for axial and rotational movement with respect to the drum, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, a lever within the drum, a pinion keyed to said rod, a rack in mesh with said pinion, means dependent upon drum movement to impart a complete oscillation to the lever, detector mechanism associated with said grippers, and means responsive to the condition 0f said detector mechanism when no sheet is carried by the grippers for coupling said rack to said lever.

18. In mechanism of the character described, a drum, sheet grippers associated with the drum, a rod axially mounted in the drum for axial and rotational movement with respect to the drum, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, a lever within the drum, a pinion on said rodl a rack in mesh with said pinion, means dependent upon drum movement to impart a complete oscillation to the lever for each revolution of the drum, detector mechanism associated with said grippers, coupling means between said lever and rack biased toward operative position, and means responsive to the condition of said detector mechanism when a sheet is carried by the grippers for disabling said coupling means.

19. In a printing machine, a printing couple. a sheet gripper comprising a bifurcated gripper finger and spaced pad lands with which the said bifurcations cooperate, a detector nger adapted to be moved by an advancing sheet into position between said lands and to be heid in that position by the closed grippers, a plunger mounted between said lands held against movement in one direction by said detector nger when the latter is held by said closed grippers, and means for effecting a throw-oil of the impression of said printing couple functioning when said plunger is i'ree to move in said direction.

cHRIsTEN R.

CORRECTION January 8, 1914.6.

CHRISTEN R. KADDELAND.

It is hereby certified that error .appears 1n the printed specification of the above numbered patent requiring correction as follows: Page T, first column, lines 5h and 55, claim 8, strike out the words "in a transversely taut condition and insert the same after "conveyor", line 55, same claim; page B, second column, line 28, claim 18, strike out for each revolution of 'die drum; and that the said Letters Patent should'be read with this correction therein that the same may conform to the record of the case in the Patent Office.

signed and sealed this 9th day er Apr-11, A. o. 19M.

(Seal) Leslie Frazer First Assistant Commissioner of' Patents.

a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillati `n to said rod, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to the rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, and impression throw-oil mechanism arranged to be set in operation by the outward movement of the rod.

15. In mechanism of the character described, a drum, sheet grippers associated with the drum, a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillation to said rod, connections between the drum and the rod for reciprocating the rod when it is oscillated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to said rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, and impression throw-ofi mechanism arranged to be set in operation toward impression-off position by the outward movement of the rod, said throw-oil mechanism comprising means for automatically maintaining itself in impression-off position during the inward movement o! the rod.

16. In mechanism of the character described. a drum, sheet grippers associated with the drum, a rod axially mounted in the drum means dependent upon drum movement operable to impart a complete oscillation to said rod, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, detector mechanism associated with said grippers, said means for imparting oscillation to said rod being responsive to the condition of said detector mechanism when no sheet is carried by the grippers, impression throw-oil mechanism arranged to be set in operation toward impression-oil' position by the outward movement of the rod, said throwoil' mechanism comprising means for automatically maintaining itself in impression-off position during the inward movement of the rod, and means for automatically shifting the throw-oli UERTIF GATE Gif Patent No. 2,592,591.

mechanism to impression-on position when the rod fails to rotate.

17. In mechanism of the character described, a drum, sheet grippers associated with the drum. a rod axially mounted in the drum for axial and rotational movement with respect to the drum, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, a lever within the drum, a pinion keyed to said rod, a rack in mesh with said pinion, means dependent upon drum movement to impart a complete oscillation to the lever, detector mechanism associated with said grippers, and means responsive to the condition 0f said detector mechanism when no sheet is carried by the grippers for coupling said rack to said lever.

18. In mechanism of the character described, a drum, sheet grippers associated with the drum, a rod axially mounted in the drum for axial and rotational movement with respect to the drum, a coarse screw connection between the drum and the rod for moving the rod lengthwise when it is rotated relative to the drum, a lever within the drum, a pinion on said rodl a rack in mesh with said pinion, means dependent upon drum movement to impart a complete oscillation to the lever for each revolution of the drum, detector mechanism associated with said grippers, coupling means between said lever and rack biased toward operative position, and means responsive to the condition of said detector mechanism when a sheet is carried by the grippers for disabling said coupling means.

19. In a printing machine, a printing couple. a sheet gripper comprising a bifurcated gripper finger and spaced pad lands with which the said bifurcations cooperate, a detector nger adapted to be moved by an advancing sheet into position between said lands and to be heid in that position by the closed grippers, a plunger mounted between said lands held against movement in one direction by said detector nger when the latter is held by said closed grippers, and means for effecting a throw-oil of the impression of said printing couple functioning when said plunger is i'ree to move in said direction.

cHRIsTEN R.

CORRECTION January 8, 1914.6.

CHRISTEN R. KADDELAND.

It is hereby certified that error .appears 1n the printed specification of the above numbered patent requiring correction as follows: Page T, first column, lines 5h and 55, claim 8, strike out the words "in a transversely taut condition and insert the same after "conveyor", line 55, same claim; page B, second column, line 28, claim 18, strike out for each revolution of 'die drum; and that the said Letters Patent should'be read with this correction therein that the same may conform to the record of the case in the Patent Office.

signed and sealed this 9th day er Apr-11, A. o. 19M.

(Seal) Leslie Frazer First Assistant Commissioner of' Patents. 

